Antidetonating combustion-chamber cylinder head



April 7, 1931. F. A. BULLINGTON ANTIDETONATING COMBUSTION CHAMBER CYLINDER HEAD Filed Nov. 12, 1928 INVENTOR. Frank A Bel/Myra A TTORNEX Patented Apr. 7, 1931 UNITED; STATES PATENT ormcr.

A. BULLINGTON, OF KANSAS CITY, MISSOURI, ASSIGNOR TO BUIJLINGTON EN- GINE HEADS, OF KANSAS CITY, MISSOURI, A. COMMON-LAW TRUST CONSISTING OF HENRY C. TAMMEN, HOWARD I. TREADWAY, AND FRANK A. IBULLINGTON' ANTIDETOHATING COMBUSTION-CHAMBER CYLINDER HEAD Application filed November 12, 1928. Serial No. 318,966.

spark plug. It is also a purpose of my invention to provide means associated with a combustion chamber of the above mentioned character extending over the end of the cylinder for distributing initial combustion pressure substantially uniformly over the head of the piston operating in said cylinder at the time of initial combustion, said means being so arranged as to subdivide the terminal combustion and to diffuse the pressure wave of said terminal combustion to thereby prevent the occurrence of detonation. A form of such means is shown in my copending application Serial #318,965 filed November 12, 1928, there being, however, certain difference in structure and function in the combustion chamber and distributing means shown in this application that have certain advantages and are improvements over the construction shown in said above mentioned copending application. By terminal combustion is meant the burning of the last portion of the fuel charge, which is usually that portion most remotely located with relation to the spark plug, or that portion of the fuel charge which is considerably diluted with inert gas remaining in the combustion chamber after a preceding explosion, and detonating combustion as commonly encountered in high compression engines, particularly when employing ordinary gasoline for fuel, is commonly associated with said terminal combustion.

The means for preventing detonation incorporated in this. application are difierent in form and arrangement and introduce certain new principles and improved features over what is shown in said copending ap-- plication, one of said features being the provision of a combustion chamber including means of an annular form for the relative isolation or retention of a portion of the inert burned gas during the suction stroke of the piston, said means being in the form of an annular recess forming a portion of the combustion space. The annular pocket or recess is formed preferably substantially concentric, relative to the spark plug, and is arranged to extend over the valves and to overlap the end of the cylinder at one side thereof. Preferably, and in the arrangement shown in the drawing, said annular chamber or pocket is formed so as to extend in an inclined or sloping manner in relation to the axis of the cylinder, so that the valve pocket combustion chamber of the engine will have a greater capacity in that portion thereof which overlaps the end of the cylinder and a smaller capacity for that portion thereof overlying the valves.

By providing the annular form for the groove or pocket forming the cushioning chamber the spark terminals of the ignition means may be so located, and are preferably so located, as to lie substantially at the geometrical center of the chamber formed by i with a mlnlmum amount of mingling with the inert gas contained in the annular portion of the combustion chamber overlying the cylinder, said inert gas in this portion of the chamber being then subject to the cooling effect of the cooling medium provided around the surrounding wall portion of said annular pocket or chamber. The comparative isolation and cooling of the inertgas during the intake stroke of the piston, during which fresh fuel is drawn into the cylinder, will efiect greater volumetric efiiciency, for the engine. The annular form of the; groove and the particular cross sectional shape 'of the annulus will be particularly effective in this respect, and it will be noted, upon referring to the drawings, that the area of the wall in contact with the gas in the annular pocket or recess is relatively large in proportion to its cross sectional area, particularly at the inner portion thereof, or the portion more remote, from the opening leading into the same from the remainder of the combustion chamber. During compression the fuel will be displaced from the cylinder into the annular portion of the combustion chamber in a manner to cause turbulence and thor-, oughly mix the fresh fuel mixture and the residual inert burned gas in said annular portion of the combustion chamber.

A purpose of my invention, in providing the annular' form ,of recess or pocket in a combustion'chamber, is to provide such a combustion chamber that any differential in the richness of compressed fuel charge contained in said combustion chamber at the time of ignition will occur in such a manner that the leaner portion of the charge will be contained in the annular portion of the combustion chamber and more particularly in that portion of the annular recess most remote from the spark plug. As the annular recess is formed so that the annular cross section thereof diminishes in a direction toward the closed inner end wall thereof, the terminal portion of the charge contained therein, or that portion most remote from the ignition means lying adjacent the closed inner end wall of the annular recess, will be of a relatively small section with a relatively large wall area adjacent thereto. With the condition of fuel mixture referred to above, terminal combustion will occur in this small section of the annulus, the fuel content of which is distributed over a relatively large circumferential distance and will be substantially equidistant from the point of initial ignition of the fuel charge, whereby no relatively large mass of fuel mixture is subject to terminalcombustion and the associated tendency toward detonation. Thus the annular portion of the combustion chamber comprises means for distributing terminal combustion, for cooling the fuel mixture in which terminal combustionoccurs, and anti-detonation means for said combustion chamber.

While the pressure distribut-in means over the cylinder head referred to a ove, is particularly effective to distribute the initial combustion pressure to that portion of the cylinder most remote from the valve pocket combustion chamber, and to divide the terminal combustion pressure Wave into components, it is a purpose of my present invention to utilize the pressure distributing means during the compression stroke, and particularly toward the end of said stroke, to effect turbulence in the combustion chamber, said means being so formed as to cause a cross stream of fuel to be directed in said combustion chamber toward the spark plug terminals.

The pressure distributing means preferably comprises a substantially centrally located transverse supply channel and means associated/therewith extending over the portion of the cylinder most remote from the valve pocket-chamber so as to distribute initial combustion pressure substantially uniformly over theportion of the head of the piston most remote from the valve pocket chamber and so arranged as to divide the terminal combustion pressure wave into comporients acting in a direction away from each other. Said distributing means preferably comprises grooves extending in divergent relation-from the central supply channel so as to direct the flow of pressure, and particularly the above mentioned divisions of the terminal combustion wave, away from each other. The central supply channel and the grooves referred to, preferably, radiate from substantially the axial center of the cylinder and the grooves 50 distribute combustion pressure over the half of the piston head most remote from the valve chamber that a substantially balanced application of explosion pressure to the piston results.

The pressure distributing means is preferably constructed so as to decrease in cross sectional area away from the valve pocket chamber, the progressively decreasing cross sectional area of the grooves toward the extremities thereof is provided to progressively diminish the fuel content of the grooves as combustion progresses toward the extremities thereof to effect terminal combustion in a minimum quantity of charge. Furthermore, the walls of said grooves serve as cooling means for the portion of the charge therein, being particularly efi'ec-tive'for this purpose at the shallow ends thereof. Said grooves thus serve as terminal combustion cooling and diffusing means constituting a means to effect anti-detonation operation for a high compression engine. Such combustion pressure distributing means is shown in a broad sense in my application, Serial #249,892, filed January 27, 1928, and the distributing means in the present invention, constitutes an improvement over the distributing means shown in said above referred to application.

Other objects and advantages of the invention will appear as the description of the drawings procecds' I desire to have it understood, however, that I do not intend to limit myself to the'details of structure shown or described, but that I intend to include as part of my invention, all such obvious changes and modifications as would occur to a person skilled in this art and as would fall within the scope of the claims.

In the drawings.:

Fig. 1 is a vertical sectional view through the cylinder head "and the portion'of the cylinder block adjoiningthe same, the lower portion of the cylinder block being broken away, said section being taken substantially on the line corresponding to line 11 of Fig. 2.

Fig. 2 is a fragmentar bottom plan view of the cylinder head, t e position of the valves and the cylinder relative thereto, when the cylinder head is in position, being showndiagrammatically in dotted lines thereon.

Fig. 3 is a section taken on the line 33 of Fig. 1 looking in the direction of the arrows, the spark plug being omitted, and

Fig. 4 is a view similar to Fig. 1 of a modification,

Referring in detail to the drawin s, my improved cylinder head is shown as eing applied to a cylinder block having a cylinder 10 in which the piston 11 operates in the usual manner. The cylinder is shown as being provided with a space 12 for cooling medium and the inlet and exhaust valves are mounted in said cylinder block, said valves being shown diagrammatically in Fig. 2, the inlet valve 13 being also shown in Fig. 1, the exhaust valve 14 being similar to the valve 13 and being shown only in Fig. 2. The valve 13 controls communication between the engine cylinder 10 and the intake passage 15.

Associated with said cylinder block is a cylinder head 16, which is provided with the space 17 for cooling medium and which is further provided with a valve pocket combustion chamber 18. The combustion chamber 18 I overlaps the cylinder at 19, at one side thereof and is provided with an annular grooved portion .20 forming an annular pocket or recess in the combustion chamber 18. The groove 20 is so arranged that the axial center line thereof is inclined at an oblique angle to the longitudinal axis of the. cylinder 10, the said center line being inclined away from the cylinder axis, whereby the portion of the groove 20 overlapping the cylinder is spaced at a greater distance fromthe top face of the cylinder block than that portion of the groove 20 adjacent the wall 21 of the valve pocket combustion chamber most remote from the cylinder, the combustion chamber having an annular portion gradually decreasing in depth from the portion of said groove over the cylinder around the same in opposite di-. rections to the portion thereof most remote from the cylinder. By this arrangement the greatest portion of the combustion space in the combustion chamber 18 is in that portion of the same adjacent the cylinder 10 and the smallest portion thereof is adjacent the wall portion 21 and over the valves.

The valve pocket combustion chamber is 'providedwith suitable ignition means 22 shown as being in the form of a spark plug mounted in the threaded opening 23 provided in the cylinder head therefor, said opening being coaxial with the annular groove 20, whereby the spark plug terminals 24 are located substantially on the axial center line of the said annular groove, said terminals being located in the valve pocket combustion chamber 18 near the opening of the valve pocket combustion chamber into the cylinder.

The cylinder head is provided with a restricting fiat wall portion 25 overlying the cylinder and having mechanical clearance from the head portion 26 of the piston 11, when the same is at the end of its compression stroke, the restricting fiat wall portion serving to restrict the application of initial combustion pressure to the piston head. The restricting wall portion 26 is shown as being in substantial alignment with the fiat face 27 on the cylinder head cooperating with the fiat face 28 on the cylinder block to clamp the gasket 29 therebetween.

The annular groove 20 is provided with a closed inner annular end wall 30 and the groove gradually decreases in width from the opening leading into the chamber 18 from said groove to said closed end wall 30. Said groove is further provided with an outer annular wall portion 31 that extends substantially parallel to the axis of the cylinder 10, and with a sloping inner annular wall portion 32 curving gradually to the substantially fiat wall portion 33 in which the spark plug 22 is mounted.

The groove 20 thus extends around the spark plug and is concentric therewith and corresponding portions of the groove at any point therein are located equidistantly from the ignition means,.the most remote portions of the groove adjacent the end wall 30 being, consequently, spaced the same distance from the ignition means all the way around the same. This provides the spreading over a large area in a thin layer of the portion of the charge in which terminal combustion occurs.

The groove 20 will contain inert hot gas when the intake stroke of the piston 11 be gins, and the incoming fresh fuel mixture will not mingle to any extent with the contents of that portion of the groove overlying the cylinder but will pass by the same into the cylinder 10. Thus the inert hot burned gas is isolated therein from the fresh fuel charge and the inert gas in this portion of the groove is cooled due to being in contact with a relativelylarge cooling surface provided by the walls of the groove, whereby the thermal efficiency of the engine is increased. When the compression stroke of the piston takes place turbulence is set up in the groove and the inert gas therein is mixed with the fresh fuel mixture entering the same, displacing some of the inert gas from the groove into the remainder of the combustion chamber where it mingles with the fuel mixture therein. Thus a combustible mixture is provided inthe valve pocket comtherein, but the proportion of inert gas in the mixture in the annular groove is greater than in the mixture in the main portion of the valve pocket combustion chamber thus providing a leaner, slower burning combustible mixture in the annular groove or recess'than in the main portion of the valve pocket combustion chamber.

In addition to the annular pocket or recess 20 serving as a combustion pressure cushioning and explosion wave absorbing chamber, combustion pressure distributing and explosion wave diffusing means is provided in the flat restricting wall portion 25 of the cylinder head. Said means comprises a supply passage 34 extending from the valve pocket chamber'18 and distributing grooves 35 leading from said supply passage. The supply passage 34 is preferably centrally arranged and the grooves 35 diverge therefrom, and in the embodiment shown the passage 34 extends substantially on the transverse diameter of the cylinder from the valve pocket chamber 18 to a point substantially over the axial center of the cylinder and the grooves 35 diverge symmetrically therefrom and extend substantially radially from near the axis of the cylinder.

It will be noted that the passage 34 dccreases in depth away from the valve pocket chamber and that the grooves 35 decrease in depth from the central point of supply from the passage 34 to the extremities 36 thereof. Said extremities are rounded as will be evident from Fig. 2 and lie substantially in alignment with the wall of the cylinder 10, said extremities having the walls thereof curved in all directions, as will be evident from Figs. 1, 2 and 3.

The passage 34 constitutes a restricted opening from the valve pocket chamber into the pressure distributing grooves, thus caus-, ing a differential in the pressure to exist between the valve pocket chamber 18 and grooves 35 when initial combustion takes place. The Walls 37 at the entrance to the groove 34 are rounded to provide for the -m0re ready passage of some of the contents of valve pocket chamber 18 into said passage 34.

Due to the provision oft-he inclined inner end wall 38 of the passage 34, the fresh fuel mixture in the cylinder will, during the compression stroke, and particularly near the end thereof, be directed toward the ignition terminals 24 and transversely across the annular groove 20 to provide a crosscurrent of fresh fuel mixture across the chamber 18 to create turbulence therein.

The arrangement of the grooves 35 will serve to provide a substantially uniform distribution of initial combustion pressure over the half of the piston head 26 remote from the valve chamber and under the restricting wall portion 25 and also provides for the diffusion of terminal combustion pressure and the directing of the terminal combustion pressure waves away from each other.

In Fig. 4 a somewhat modified form 0 cylinder head is shown for use on a relatively short stroke engine, particularly'when high compression is employed, in which case the combustion chamber is of necessity relatively small. The construction 'of the cylinder head is substantially the same as previously described, except for the formation of the annular grooved portion of the valve pocket chamber and the proportions of the combustion chaimber itself.

The parts that are substantially the same in Fig. 4 as in Figs. 1. to 3, inclusive, are indicated by the same numerals in Fig. 4 as in said figures. The principal difference between the cylinder head 16 shown in Fig. 4

and the head 16 shown in Figs. 1 to 3, incluthereof in alignment with' the transverse diameter of the cylinder, and overlying said cylinder, to the portion of the valve pocket chamber mostremote from the cylinder. Due to the provision of the annular groove, the wall portion 33 can be placed much nearer the top face of the cylinder block than would be otherwise possible as the annular groove 20 will be of such size as to provide suflicient capacity for the unobstructed flow of the gases to and from the cylinder. The annular groove is made of a relatively small capacity in this form of the invention and the groove 20 is arranged to lie with its axis at a much smaller angle to the axis of the cylinder than in the form shown in Figs. 1 to 3, inclusive, but is inclined suiiiciently to place the portion of the valve pocket chamber 'of relatively greater capacity overlapping the cylinder. The groove 20 is of similar shape in cross section .to the groove 20, tapering toward the wall portion 30 thereof, but decreasing in depth from that portion thereof over the cylinder to the portion remote from the cylinder. It will be obvious that the inclination of the annular groove 20 may be varied as desired to obtain the desired form and size of combustion chamber in the cylinder head. The action and purpose of the annular groove or recess is substantially the same in both forms of the invention.

Having thus described my invention, what I desire'to claim and secure by United States Letters Patent is:

scribed, having a valve pocket recess therein provided with an annular chambered portion, said annular chambered portion gradually decreasing in depth from a relatively deep portion thereof at one side of said recess to a relatively shallow portion at the opposite side of said recess.

3. A cylinderaihead of the character described, having a valve pocket recess therein provided with an annular groove portion, and combustion pressure distributing means extending from said recess in said cylinder head comp-rising diverging grooves remote from said recess. v

4. In an internal combustion engine, a cylinder and a cylinder head having a valve pocket combustion chamber therein and hav ing a restricting wall portion overlying said cylinder, said head having combustion pressure distributing means overlying said cylinder, said means comprising diverging grooves in that portion of said restricting wall portion overlying the portion of the cylinder remote from the valve pocket chamber, said grooves decreasing in cross sectional agea toward the divergent extremities there- 0 g 5. In an internal combustion engine. a cylinder and acylinder head having a valve pocket combustion chamber therein, and having combustion pressure distributing means overlying said cylinder, said means comprisingdiverging grooves overlying that portion ofthe cylinder remote from the valve pocket chamber and a groove extending from said valve pocket chamber to said diverging grooves and opening into the same.

6. In an internal combustion engine. a cylinder and a cylinder head having a valve nocket combustion chamber therein, and having combustion pressure distributing means 1 overlving said cylinder, said means comprising diverging grooves overlying that portion of the cylinder remote from the valve pocket chamber and a substantially centrally arranged groove extending from said valve pocket chamber to said diverging grooves and opening into the same.

7. In an internal combustion engine, a cylinder and a cylinder head having a valve pocket combustion chamber therein, and having combustion pressure distributing means overlying said cylinder, said means comprising diverging grooves overlying that portion of the cylinder remote from the valve pocket chamber and a groove extending from said valve pocket chamber to said diverging grooves and opening into the same, said grooves gradually decreasing in cross sectional area away from said valve pocket chamber.

8. In an internal combustion engine, a cylinder and a cylinder head having a valve pocket combustion chamber therein, and having combustion pressure distributing means overlying said cylinder, said means comprising diverging grooves overlying that portion of the cylinder remote from the valve pocket ,chamber and a connecting groove extending from said valve pocket chamber to said diverging grooves and opening into the same, said grooves diverging substantially symmetrically away from said connecting groove.

9. In an internal combustion engine, a cylinder and a cylinder head having a valve pocket combustion chamber therein, said valve pocket chamber having an annular recess therein, and said cylinder head having combustion pressure distributing means overlying said cylinder, said means comprising diverging grooves overlying that portion of thecylinder remote from the valve pocket chamber. p

10. In aninternal combustion engine, a cylinder and a cylinder head having a valve pocket combustion chamber therein, said valve pocket chamber having an annular groove therein, and said cylinder head having a grooved restricting wall portion overlying said cylinder.

11. In an internal combustion engine, a cylinder, valves at one side of said cylinder, and a cylinder head having a valve pocket combustion chamber therein overlapping one side of said cylinder, said valve pocket cha1nher having an annular recess therein defining a projecting wall portion in said head surrounded by said recess, said recess extending over said valves and said cylinder.

12. In an internal combustion engine, a cylinder, valves at one side of said cylinder, a cylinder head, and ignition means in said cylinder head, said cylinder head having a combustion chamber therein overlying said valves and overlapping one side of said cylinder, said chamber'having an annular recess therein defining a projecting wall portion in said head in which said ignition means is mounted surrounded by said recess.

13. In an internal combustion engine, a cylinder and a cylinder head having a valve pocket combustion chamber therein, and a restricting wall portion in said head overlying the cylinder, said restricting wall portion having combustion pressure distributing means overlying said cylinder, said means comprising diverging grooves in said restricting wall portion overlying that por- III tion of the cylinder remote from the valve pocket chamber.

14. In an internal combustion engine, a cylinder, a cylinder head,valves at one side 6 of said cylinder, and ignition means in said cylinder head, said cylinder head having a combustion chamber therein having an annular groove extending over said valves and around said ignition means, the transverse 10 section of said groove decreasing in width toward the bottom thereof.

15. In an internal combustion engine, a cylinder, a cylinder head, valves at one side of said cylinder, and ignition means in said 15 cylinder head, said cylinder head having a combustion chamber therein, having an annular recess therein defining ,a projection surrounded by said recess, said recess extending over said valves and gradually narrow- 20 ing from the annular opening of said recess into the remainder of the combustion chamher to the closed annular end wall thereof.

In testimony whereof, I hereunto subscribe my name this 8th day of November, 1928.

' FRANK A. BULLINGTON.

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